{"id":"F2006B03162","name":"AD/B747/266 - Flight Engineers Panel Wire Bundle Clamping","slug":"ad-b747-266-flight-engineers-panel-wire-bundle-clamping","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42534,"registerId":"commonwealth-F2006B03162-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/266 - Flight Engineers Panel Wire Bundle Clamping","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\n \n\n![](image.001.png)\n\n# AIRWORTHINESS DIRECTIVE\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)\n\n \n\nBoeing B747 Series Aeroplanes\n\n \n\n# AD/B747/266 Flight Engineer’s Panel Wire Bundle Clamping\n\n\n2/2002\n\n \n\nApplicability: Model 747-100, 747-200B, 747-200C, 747-200F, 747SP, and 747SR series aeroplanes; line numbers 001 through 310 inclusive.\n\n \n\nRequirement: 1. Perform a one-time detailed visual inspection for chafing of wire bundles in the area of the forward upper corner of the P4 flight engineer's panel, outboard of the drip shield, paying particular attention to wire bundles W528 and W530.\n\n \n\nNote 1: For the purposes of this Directive, a detailed visual inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”\n\n \n\n2.        If, as a result of the Requirement 1 inspection, any chafing is found, repair the chafed wire bundles in accordance with Section 20-10-13 of the Boeing Standard Wiring Practices Manual.\n\n \n\n3.        Modify the aeroplane by rerouting electrical wire bundle W530 to ensure sufficient clearance between that wire bundle and an adjacent flood light support bracket and installing a caterpillar grommet on the flood light supports, in accordance with Boeing Alert Service Bulletin (ASB) 747-25A2407, Revision 1, dated 23 September 1999.\n\n \n\nModifications accomplished prior to the effective date of this Directive in accordance with ASB 747-25-2407, dated 18 November 1977, are acceptable for compliance with Requirement 3. However, the detailed visual inspection required by Requirement 1 and any applicable corrective actions required by Requirement 2 must still be accomplished.\n\n \n\nWhere ASB 747-25A2407, Revision 1, specifies that installation of a caterpillar grommet may be accomplished per \"your equivalent procedure,'' the procedures must be accomplished per the applicable chapter of the Boeing 747 Overhaul Manual specified in the service bulletin.\n\n \n\nNote 2: FAA AD 2001-24-32 Amdt 39-12549 refers.\n\n \n\nBoeing B747 Series Aeroplanes\n\n \n\nAD/B747/266 (continued)\n\n \n\nCompliance: For Requirement 1 - Before 16 January 2003.\n\n \n\nFor Requirement 2 - Before further flight, following the Requirement 1 inspection.\n\n \n\nFor Requirement 3 - Before further flight, following the Requirement 1 inspection or Requirement 2 repair, as applicable.\n\n \n\nThis Airworthiness Directive becomes effective on 21 February 2002.\n\n \n\nBackground:  This Directive requires a one-time inspection for chafing of certain wire bundles behind the flight engineer's panel, together with any necessary repairs. The Directive also requires a modification to reroute a certain electrical wire bundle to ensure sufficient clearance between that wire bundle and an adjacent flood light support bracket.\n\n \n\nThese actions are necessary to prevent chafing of certain electrical wire bundles, which could result in smoke in the cockpit and an uncommanded discharge of fire extinguishing bottles for the No. 4 engine, with the consequent reduction in the ability to fight a fire in the No. 4 engine.\n\nSignature of Eugene Paul Holzapfel, Delegate of the Civil Aviation Safety Authority.\n\n![Signature of Eugene Paul Holzapfel, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\n\n \n\nEugene Paul Holzapfel\n\nDelegate of the Civil Aviation Safety Authority 14 January 2002\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n![](image.001.png)  \n\n\nThe above AD is notified in the Commonwealth of Australia Gazette on 30 January 2002.\n","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope: addressing a specific wiring safety issue on specific Boeing 747 aircraft. The document has not expanded beyond its original technical safety purpose."},"complexity_factors":["Single specific aircraft type and limited serial number range (line numbers 001-310)","Only 3 requirements with clear sequential dependencies","One defined term ('detailed visual inspection') with explicit definition provided","Simple conditional logic: 'If chafing found, then repair'","Reference to external technical documents (Boeing Service Bulletin) but with specific revision and date cited","Grandfathering clause for prior modifications (accepting earlier version of service bulletin)","No nested exceptions or complex cross-references to other legislation"],"plain_english_summary":"This safety order requires operators of specific Boeing 747 models (100/200/200B/200C/200F/SP/SR, S/N 001–310) to inspect wiring behind the flight‑engineer panel for chafing, repair any damage, and reroute/protect affected bundles (notably W528/W530) before further flight, with inspections due by 16 Jan 2003. It affects airlines, maintenance engineers and CASA enforcement and aims to prevent cockpit smoke and inadvertent engine‑extinguisher discharge."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive remains narrowly focused on the original technical problem: inspecting and correcting chafing of specific wire bundles behind the P4 flight engineer's panel and rerouting/retaining wire W530 to prevent contact with a flood light support bracket. It does not expand into unrelated systems or impose continuing inspection cycles; prior modifications under an earlier Boeing ASB are accepted only for the specific modification (Requirement 3), so the scope is consistent with the original intent and has not grown significantly beyond addressing that identified unsafe condition."},"complexity_factors":["Narrow applicability: 6 specified 747 variants and line numbers 001–310 (limited population to inspect)","Three discrete requirements (inspect, repair if found, modify/reroute) with clear sequencing","One defined inspection term (\"detailed visual inspection\") with a full definition (Note 1)","Cross-reference to external technical documents (Boeing Alert Service Bulletin 747-25A2407 Rev 1; Boeing Standard Wiring Practices Manual; Boeing 747 Overhaul Manual)","Allowance for prior compliance under an older ASB (1977 ASB accepted for Requirement 3) creates a conditional exception","Single firm compliance deadline for inspection and before-further-flight requirements for repairs and modifications","Reference to FAA AD (external regulatory cross-reference) but no extensive multi-part conditional logic"],"plain_english_summary":"**What this directive does (mechanics)\n\n- Affects: Boeing 747 models 747-100, 747-200B, 747-200C, 747-200F, 747SP and 747SR, line numbers 001–310 inclusive (Applicability).\n\n- Immediate actions required:\n  - Do a one-time, detailed visual inspection for chafing of wire bundles at the forward upper corner of the P4 flight engineer's panel, outboard of the drip shield — pay particular attention to wire bundles W528 and W530 (Requirement 1; Note 1 defines \"detailed visual inspection\").\n  - If any chafing is found, repair the chafed wires before the next flight using Boeing's Standard Wiring Practices Manual (Requirement 2).\n  - Reroute wire bundle W530 to provide adequate clearance from a nearby flood light support bracket, and install a caterpillar grommet on the flood light supports, following Boeing Alert Service Bulletin 747-25A2407, Revision 1 (Requirement 3). Modifications done earlier under the older ASB (dated 18 November 1977) are acceptable for Requirement 3, but the inspection (Requirement 1) and any repairs (Requirement 2) still must be done.\n\n- Timing (Compliance):\n  - The inspection must be completed before 16 January 2003 (Requirement 1).\n  - Any repairs found by that inspection must be done before the aircraft’s next flight (Requirement 2).\n  - The reroute and grommet installation must also be done before further flight after the inspection or repair (Requirement 3).\n\n- Administrative/legal points:\n  - The directive became effective 21 February 2002.\n  - The AD refers to a related FAA directive (FAA AD 2001-24-32) and to Boeing service documents for the technical instructions (Note 2; Requirement 3).\n\nWhy the rule exists (stated safety rationale)\n\n- The stated purpose is to prevent chafing of the identified wire bundles. Chafed electrical wiring in that area could produce smoke in the cockpit and could cause an unintended discharge of the No. 4 engine fire-extinguishing bottles. An unintended discharge would reduce the ability to fight a fire in the No. 4 engine.\n\nPractical effects, costs and decision points (testing the stated purpose against incentives and trade-offs)\n\n- Who pays: aircraft operators/owners pay for the inspection, any repairs, the reroute and installation of grommets, plus associated labour and aircraft downtime.\n\n- Who decides how to comply: the AD prescribes inspection and repair standards and directs operators to Boeing's Alert Service Bulletin and the Boeing Standard Wiring Practices Manual. Where the ASB allows \"your equivalent procedure,\" the AD requires use of the Boeing 747 Overhaul Manual chapter cited by the ASB (Requirement 3).\n\n- Behaviour changes required: operators must schedule and complete a one-time targeted inspection, repair any chafed wiring before flight, and implement a wiring reroute plus grommet installation.\n\n- Compliance burden and implementation risk: the inspection is a \"detailed visual inspection\" (requires good lighting, possible use of mirrors/magnifiers and surface cleaning) and may need access that takes aircraft out of service. The reroute and caterpillar grommet installation are physical modifications that may require parts, trained technicians, and time in a maintenance facility. Operators who previously complied with the older ASB are partially exempt from repeating the modification but still must inspect and repair.\n\n- Trade-offs and substitution effects: because the requirement is one-time, operators are likely to combine the work with scheduled maintenance where possible to reduce downtime. The directive imposes a short-term cost (inspection/repair/modification) to reduce an identified safety risk.\n\n- Enforcement implication: until the inspection/modification is done, affected aircraft are not in compliance with the AD and therefore not airworthy under the regulation cited.\n\n- Cross-reference and consistency: the AD relies on Boeing service instructions for the technical fix and references an FAA AD that addresses the same issue (Note 2). The AD accepts an earlier Boeing ASB as an alternative for the modification, subject to still doing the inspection and repairs.\n\nKey citations inside the directive: Requirement 1 (inspection), Note 1 (definition of detailed inspection), Requirement 2 (repair), Requirement 3 (reroute and grommet; reference to ASB 747-25A2407 Rev 1), Compliance dates, Background (safety rationale)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-266-flight-engineers-panel-wire-bundle-clamping","history":"/api/acts/ad-b747-266-flight-engineers-panel-wire-bundle-clamping/history","analysis":"/api/acts/ad-b747-266-flight-engineers-panel-wire-bundle-clamping/analysis","conflicts":"/api/acts/ad-b747-266-flight-engineers-panel-wire-bundle-clamping/conflicts","importantCases":"/api/acts/ad-b747-266-flight-engineers-panel-wire-bundle-clamping/important-cases","documents":"/api/acts/ad-b747-266-flight-engineers-panel-wire-bundle-clamping/documents"}}